Fix comments in asm with JitDiffableDasm=1 (#56416)

* Avoid asserts in DasmDiffable mode

* simplify

* Make formatter happier

* Address feedback

Author: EgorBo

src/coreclr/jit/emit.cpp

@@ -3936,7 +3936,7 @@ void emitter::emitDispCommentForHandle(size_t handle, GenTreeFlags flag)
         // NOTE: eGetCPString always returns nullptr on Linux/ARM
         if (wstr == nullptr)
         {
-            printf("%s string handle", commentPrefix);
+            str = "string handle";
         }
         else
         {

src/coreclr/jit/emitxarch.cpp

@@ -8851,6 +8851,7 @@ void emitter::emitDispIns(
             else
             {
             PRINT_CONSTANT:
+                ssize_t srcVal = val;
                 // Munge any pointers if we want diff-able disassembly
                 if (emitComp->opts.disDiffable)
                 {
@@ -8872,8 +8873,7 @@ void emitter::emitDispIns(
                 { // (val < 0)
                     printf("-0x%IX", -val);
                 }
-
-                emitDispCommentForHandle(val, id->idDebugOnlyInfo()->idFlags & GTF_ICON_HDL_MASK);
+                emitDispCommentForHandle(srcVal, id->idDebugOnlyInfo()->idFlags & GTF_ICON_HDL_MASK);
             }
             break;